Meaning of failure symbol at startup

[BlueMacawBird]

I've been offered a vintage iMac (looks like a 7,1 or maybe an 8,1). It fails to start, and displays a circle and bar on a gray screen. I've seen the failure symbol of a blinking folder, indicating that no operating system can be found, but I'm not sure about the circle and bar. Does that indicate a hardware failure other than a lack of an operating system? I don't want to buy the machine if that's the case.

Thanks,

John

 

[Saturnine]

If your Mac starts up to a circle with a line through it - Apple Support

support.apple.com

This says that macOS has been found but it's a version incompatible with the machine on which its installed. It suggests booting up in Recovery Mode and reinstalling the operating system.

I also believe a failed hard drive/SSD can cause this. They're fairly easy to replace on those iMac though. Take off the plastic screen which suction cups (it's held on magnetically), unscrew a few Torx screws and from their it's obvious. Just have to be a bit careful not to damage the ribbon cables connecting the screen as you open it. Anybody with a little bit of experience of opening up electronics could do it.

 

[DeltaMac]

Just a caution here. The screen front is glass, not plastic, and it is thin plate glass that can be quite fragile, so take care when removing -- be careful how you store it while it is removed.
And, the internals are not as obvious as Saturnine seems to think.
iFixit.com has good "opening-up" steps that will help you with the internals, such as replacing an older hard drive with an SSD.
Also, an older iMac might not have been upgraded to a system that has a Recovery partition (worked on a 2007 recently that was still on the original Tiger, which was never updated at all since new. Owner never connected to internet, only used it to store and edit photos and personal records. And, hard drives eventually fail...
The point is, a recovery mode reinstall is not always available. (Internet recovery also is not on those older iMacs, not until 2011 models ). That probably explains why I keep a box full of OS X/macOS bootable USB installers...

 

[BlueMacawBird]

Thanks to all for the replies. I am all too familiar with working on iMac machines and I know that this one is not too bad to open up. I think the all time worst would be a toss-up between the 21.5" machines with the displays bonded to the body of the computer, and the G4 iMac, which is no fun at all. In any event I would want to put an SSD in the machine anyway. I did want to be sure the circle with bar did not mean a hardware failure in the machine, beyond possibly a hard disk failure.

Another great source for repair videos is OWC; they have lots of good videos showing how to take machines apart and perform upgrades. I view those all the time.

John

 

[Saturnine]

Just a caution here. The screen front is glass, not plastic, and it is thin plate glass that can be quite fragile, so take care when removing -- be careful how you store it while it is removed.
And, the internals are not as obvious as Saturnine seems to think.
iFixit.com has good "opening-up" steps that will help you with the internals, such as replacing an older hard drive with an SSD.
Also, an older iMac might not have been upgraded to a system that has a Recovery partition (worked on a 2007 recently that was still on the original Tiger, which was never updated at all since new. Owner never connected to internet, only used it to store and edit photos and personal records. And, hard drives eventually fail...
The point is, a recovery mode reinstall is not always available. (Internet recovery also is not on those older iMacs, not until 2011 models ). That probably explains why I keep a box full of OS X/macOS bootable USB installers...

The internals are absolutely as obvious as Saturnine seems to think. If you open up the machine and don’t think it’s straightforward, you have no business being in there.

Having said that, I absolutely agree that using a teardown guide is a sensible precaution.

 

[DeltaMac]

Yes, unfortunately --- I have found myself too many times, following up with some of those users who (too quickly) opened 'er up, without thinking about some of those ribbon cables, or finding connectors after forcefully removing them... and, in the case of these older Macs, I do my best to help the user decide if replacing that logic board/etc. is worth the effort (or money)